1. Field of Invention
The present invention relates to a connecting device. More particularly, the present invention relates to a hinge assembly.
2. Description of Related Art
Many electrical apparatuses have devices which can be moved or rotated relative to each other. For example, the display screen of a mobile phone with a clam structure can be rotated relative to the base of the mobile phone. Two traditional kinds of hinge assemblies are available for providing electrical connections that can be rotated.
The first kind is the hollow type hinge assembly. An electrical connecting device, such as a flexible printed circuit, passes through the hollow type hinge assembly to electrically connect two devices, which can be rotated relative to each other. This limits the size of connectors configured on both sides of the flexible printed circuit because the connectors need to pass through the hollow type hinge assembly. The size of the connector becomes more and more difficult to design as the size of modern electrical apparatuses becomes smaller and smaller.
The second kind is the winding type hinge assembly. A flexible printed circuit is wound around the hinge assembly between two devices, which the hinge assembly is mounted on, to electrically connect those two devices. However, the winding type hinge assembly is difficult to assemble, especially due to winding the flexible circuit to electrically connect devices. Moreover, the inevitable friction between the flexible printed circuit and the hinge assembly during the rotation operation easily wears the flexible printed circuit.